Gas chromatographic and mass spectrometric methods for the characterisation of long-chain fatty acids: Application to wool wax extracts Review Article

A review of the existing methods for the separation, identification and quantification of fatty acids mainly by chromatography and mass spectrometry (MS) techniques is presented. Moreover, a method for the simultaneous determination of the following lipidic classes, which are constituents of the wool wax, namely fatty acids, fatty alcohols, 2-hydroxy fatty acids and 2-hydroxy fatty alcohols have been developed. Every compound class consist of normal-, iso- and anteiso-branched chain isomers. The separation of all molecular species, in the range of carbon atom number C8–C33 was achieved on a low polar capillary gas chromatograph (GC) column. Compound identification has been made by interpretation of mass spectra of mono- and di-tandem mass spectrometry (TMS) derivatives as well as on the basis of equivalent (ECL) and fractional chain length (FCL) retention parameters. The relative abundance of every compound class has been obtained as a function of carbon atom number.